Recent evidence has suggested that lung volume reduction surgery (LVRS) may be a useful therapeutic option for pateints with end stage emphysema. Preliminary data has suggested the LVRS may improve lung elastic recoil as well as respiratory muscle function thereby improvong air flow and exercise tolerance in patients with severe emphysema. In certain individuals this has translated into substantially improved quality of life. However numerous questions remain regarding the surgery including whether or not the improvement in lung function is longlasting and what precisely are the risks/benefits of the procedure. Furthermore, numerous questions remain regarding the appropriate screening tests and the ideal patients that should be selected for this type of surgery. In order to address these questioins, a multi-center study has been funded by the NIH and the Health Care Financing Administration. The Ohio State University Medical Center has abeen selected as one of 18 centers participating in this randomized clinical trial.